Adjustable tremolo device



March l1, 1930. a. E. MILLS 1,750,325

ADJUSTABLE 'REMOLO DEVICE Filed June 2, 1928 2 Sheets-Shen l March 11, 1930. B. E. MILLS 1,750,325

ADJUSTABLE TREMoLo DEVICE Filed June 2. 1928 2 Shoots-Sheet 2 Patented Mar. 11, 1930 UNITED STATES PATENT OFFICE BERT E. MILLS, OF OAK PARK, ILLINOIS, ASSIGNOR TO MILLS NOVELTY COMPANY, F CHICAGO, ILLINOIS, A CORPORATION 0F ILLINOIS ADJUSTABLE TREMOLO DEVICE Application led June 2, 1928.

This invention relates to tremolo devices for stringed musical instruments, such, for example, as an electrically-operated violin or cello, and has for its principal object the provision of an improvement in such devices which renders the operation of the tremolo device subject to the control of the operator during the playing of the instrument, so that the tremolo effect may be varied from time to time as the operator may desire.

Other objects and advantages of the invention will be apparent as it is better understood from the following description, which, taken in connection with the accompanying drawings, discloses a preferred embodiment thereof.

Referring to vthe drawings,

Figure 1 is an elevational view of a portion of the instrument showing the string tensioning means and the pulsating devices therefor, the latter being shown in part sectionally;

Fig. 2 is a plan view of the pulsating devices and the conduits serving the same, taken substantially on the plane 2-2 of Fig. 1, this view showing also, in dotted lines, the pump and the connection between the latter and said conduits;

Fig. 3 is a plan view of the pump and the control devices therefor; and

Fig. 4 is a sectional view thereof, taken substantially on the section line 4-4 of Fig. 3.

Upon said drawings, illustrating the preferred exempliiication of the invention, the reference character 5 indicates the neck portion of a violin or cello, which is mounted in a frame 6 and is equipped with strings 7, each of which passes over a grooved sector 3 and is secured to an adjusting device 9 carried by a tensioning lever 10, said adjusting device being manually operable by means of a key 11.

It will be understood that there is one of the tensioning levers 1() and associated mechanism for each of the strings, although only two of said levers are shown.

The parts are so adjusted that the strings are under normal tension with the levers l() in the horizontal position, and said levers are Serial No. 282,364.

connected by links 12 with springs 13, the latter being connected at their lower ends with individual tensioning devices 14, which are adapted to be adjusted by adjusting screws 15, in obvious manner. The levers 10 are connected by piston rods 16 with pistons 1?, disposed within cylinders 18, of which there are four in number, as shown in Fig. 2. rlhe pistons 17 need not fit closely within the cylinders 6 and are adapted to be actuated by compressed air, or pulsations entering through individual conduits 19 extending through a block or valve casing 20, fitted with controlling valves 2l and having a common conduit 22 serving all of the conduits 19, said conduits 22 being, in effect, a continuation of a flexible conduit 23 leading from a pump 24 shown diagrammatically in Fig. 2.

rlhe pump is shown in detail in Figs. 3 and 4 and comprises primarily a cylinder 25, mounted in a frame 26 and having therein a pump piston 27. Said cylinder is closed at its opposite ends by means of end members 23 and 29, the former having a conduit 30 therein communicating with the flexible conduit 23.

A solenoid 31 is positioned on the exterior of the cylinder 25 and is included in a circuit represented by wires 32 and 33. A makeand-break device is also included in the circuit and consists of a spring contact member 34, mounted on an insulating block 35 secured to the frame, and a movable contact member 36 carried by an arm 37, which is pivoted at 38 to a xed point 'on the frame. The arm 3?', near the outer end thereof, has a. vertical flange 39 provided with an aperture 40, through which extends a piston rod 41, secured to the piston 27 and extending through the cylinder end plate 29, the outer end of said rod 41 having a suitable washer 42 and nut 43 fitted thereto, said washer being larger than the aperture 40 so that movement of the piston toward the left, viewing Figs. 3 and 4, will move said arm 37 on its pivot, the limit of such movement being indicated in dotted lines in Fig. 3, which show the arm against a fixed stop 44. A hook 45 is provided at the outer end of the flange 39 and an insulating link 46 connects said hook with one end of a spring 47, the opposite end of which is secured to an arm 48, pivoted at 49 to the frame and adapted to be adjusted to predetermined position by means of an adjusting screw 50. Said arm 48 is connected by means of a connection 51 with a. horizontal arm 52, carried upon a shaft 53, mounted in bearings 54 on the frame, said shaft 53 having also secured thereto a manually operable adjusting lever 55, which is preferably of such form and so positioned as to permitthe operator to actuate the same by his knee during the playing of the instrument, if the latter be manually played.

The spring 47 normally holds the arm 37 in the outer position, against an adjustable stop member 56, carried by a screw 57 extending through a fixed part 58 on the frame.

Assuming the player switch to be in the on position, the tremolo device operates as follows: The solenoid 31 actuates the piston 27 to draw the same toward the left, viewing Fig. 4, thus pumping air through the conduits 30, 23, 22, and 19 to the cylinders 18, thus momentarily lifting the pistons 17. This movement of the piston is accompanied by a breaking of the contact 34, 36 and, since the arm 37, carrying the contact 36, is moved by the piston rod 41 toward the left, as shown in Fig. 3, the solenoid is thus deenergized and the spring 47 pulls the arm 37 back to the full line position shown in Fig. 3, thus reestablishing the contact 34. 36 and again energizing the solenoid 31. which draws the piston again toward the left. producing a recurrence of the operation just described. It will be evident that this action causes a pulsating effect by rapidly raising and lowering the pistons 17 in the cylinders 18, this operation being substantially as shown in my prior patent No. 1,621,126. In accordance with my present invention, however, both the frequency and the amplitude of the piston strokes, and consequently the pulsations, may be controlled at will by the operator by manipulation of the lever 55, which, as before stated, may be conveniently positioned to permit actuation by the knee of the operator, though, of course, the invention contemplates that it may be actuated in any suitable manner.

The effect of manipulation of said lever 55 is to vary the tension on the spring 47. By increasing the tension, greater resistance is offered to the movement of the lever 37 away from the normal position shown in Fig. 3, thus tending -to limit the stroke of the piston and causing the circuit to be made and broken with greater rapidity than would be the case when the tension on the spring 47 is relaxed, thus permitting the longer stroke of the piston 27 and greater movement of the contactcarrying arm 37. The operator is thus enabled to control the tremolo effect and to vary the same as he may desire during the playing of the instrument.

It is thought that the invention and many of its attendant advantages will be understood from the foregoing description, and it will be apparent that various changes may be made in the form, construction, and arrangement of the parts without departing from the spirit and scope of the invention, or sacrificing all of its material advantages the form hereinbefore described being merely a preferred embodiment thereof.

I claim:

1. The combination with a stringed instrument of the viol class having a string tensioning device, of a tremolo device comprising a pulsating device connected with said tensioning device, a pump provided with a conduit serving said pulsating device, a solenoid serving to actuate said pump, an electric circuit for said solenoid controlled by Said pump, and a device under the control of the operator of the instrument for regulating the control of said circuit by the pump.

2. The combination with a stringed instru ment of the viol class having a string tensioning device, of a tremolo device comprising a pulsating device connected with said tensioning device, a pump provided with a conduit serving said pulsating device, a solenoid serving to actuate said pump in one direction, a spring adapted to actuate said pump in the other direction, an electric circuit for said solenoid controlled by said pump, and a manually operable device for varying the tension on said spring to thereby regulate the opera tion of the pump and the control of said circuit.

3. In combination with string tensioning levers and separate pulsating devices connected therewith, conduits leading to said pulsating devices, a pump serving all of said conduits, yielding means for controlling the 0peration of said pump, and means under the control of the operator for varying the effect of said yielding means to thereby control the action of said pump.

4. In combination with a string tensioning lever and a pulsating device connected therewith, a conduit leading to said pulsating device, a pump serving said conduit, yielding means for controlling the operation of said pump, and means under the control of the operator for varying the effect of said yielding means to thereby control the action of said pump.

5. In combination with a string tensioning device of a stringed instrument of the viol class, a tremolo device comprising a pulsating device connected with said tensioning device, a pump provided with a conduit serving said pulsating device, means for actuating said pump including a spring device, and means for varying the tension of said spring device at will to thereby control the action of the pump.

llo

6. In combination With a string tensioning device of a stringed instrument of the viol class, a tremolo device comprising a pulsating device connected With said tensioning device, a pump provided with a conduit serving said pulsating device, an electrically-operated device for actuating said pump in one direction, including an electric circuit and a makeand-break device controlled by the pump, yielding means for actuating the pump in the opposite direction, and means operable at Will during the playing o1 the instrument igor varying the tension of said yielding means to thereby vary the control of said make-andbreak device by the pump.

7. In combination With a string tensioning device of a stringed instrument of the viol class, a tremolo device comprising a pulsating device connected With said tensioning de:- vice, a pump provided With a conduit serving said pulsating device, said pump comprising a cylinder and a pump piston therein, an electro-magnetic device for actuating said piston in one direction, a spring device for actuating the piston in the opposite direction, a makeand-break device for controlling said electro-magnetic device, one element oi said make-and-break device being associated with the spring device, and means whereby the operator may vary the tension of the spring device at Will to thereby control the operation of said make-and-break device.

8. In combination With a string tensioning device oit' a stringed instrument of the viol class, a tremolo device comprising a pulsating device connected With said tensioning device, a pump provided with a conduit serving said pulsating device, said pump comprising a cylinder and a pump piston therein equipped with a piston rod protruding from said cylinder, a pivoted arm connected with said piston rod, a spring connected With said arm and adapted to actuate the piston in one direction, an electro-magnetic device for actuating the piston in the opposite direction, a circuit including a make-and-brake device, one element thereofl being carried by said arm, and a manually operable device for regulating the tension of said spring at Will whereby the operator may control the rapidity of the making and breaking of the circuit for said electromagnetic device, thus controlling the operation of the pump.

9. The combination with a stringed instrument of the viol class having a string tensioning device, of a tremolo device comprising a pulsating device connected with said tensioning device, a pump provided with a conduit serving said pulsating device, a solenoid serving to actuate said pump, an electric circuit for said solenoid controlled by said pump, and a device comprising a pivoted member adapted to be moved at will by the operator during the playing of the instrument for controlling the operation of said pump and the control of said circuit thereby.

l0. The combination With a stringed in` strument of the viol class having a string tensioning device, of a tremolo device comprising a pulsating device connected With said tensioning device, a pump provided With a conduit serving said pulsating device, a solenoid serving to actuate said pump in one direction, a spring adapted to actuate said pump in the other direction, an electric circuit for said solenoid controlled by said pump, and a manually operable device comprising a pivoted member adapted to be moved at will by the operator during the playing of the instrument to control the tension on said spring and thus regulate the action of the pump and the control of said circuit thereby.

In witness whereof, I hereunto subscribe my naine to this specification.

BERT E. MILLS. 

